$441 Cheap Flights from Seattle (SEA) to London (STN)

View $441 flight on Wed, Oct 1, 2025Opens in a new window

Popular airlines from Seattle-Tacoma International Airport (SEA) to Stansted Airport (STN)

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Find available prices by choosing your travel dates.

Cheap Flights from Seattle to London (SEA-STN)

Prices were available within the past 7 days and start at $441 for one-way flights and $2,258 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Royal Air Maroc
Tue, Jul 15 - Tue, Jul 22
SEA
Seattle
STN
London
$2,258 Roundtrip, found 4 days ago
$2,258
Roundtrip
found 4 days ago
Select Royal Air Maroc flight, departing Tue, Jul 15 from Seattle to London, returning Tue, Jul 22, priced at $2,258 found 4 days ago
Royal Air Maroc
Tue, Jul 15 - Tue, Jul 22
SEA
Seattle
STN
London
$2,282 Roundtrip, found 4 days ago
$2,282
Roundtrip
found 4 days ago
Select Royal Air Maroc flight, departing Tue, Jul 15 from Seattle to London, returning Tue, Jul 22, priced at $2,282 found 4 days ago
Royal Air Maroc
Sun, Jul 13 - Sun, Jul 20
SEA
Seattle
STN
London
$2,435 Roundtrip, found 1 day ago
$2,435
Roundtrip
found 1 day ago
Select Royal Air Maroc flight, departing Sun, Jul 13 from Seattle to London, returning Sun, Jul 20, priced at $2,435 found 1 day ago
Royal Air Maroc
Sun, Jul 13 - Sun, Jul 20
SEA
Seattle
STN
London
$2,455 Roundtrip, found 1 day ago
$2,455
Roundtrip
found 1 day ago
Select Royal Air Maroc flight, departing Sun, Jul 13 from Seattle to London, returning Sun, Jul 20, priced at $2,455 found 1 day ago
Royal Air Maroc
Sun, Jul 13 - Sun, Jul 20
SEA
Seattle
STN
London
$3,329 Roundtrip, found 1 day ago
$3,329
Roundtrip
found 1 day ago
Select Royal Air Maroc flight, departing Sun, Jul 13 from Seattle to London, returning Sun, Jul 20, priced at $3,329 found 1 day ago
Royal Air Maroc
Sun, Jul 13 - Sun, Jul 20
SEA
Seattle
STN
London
$3,392 Roundtrip, found 1 day ago
$3,392
Roundtrip
found 1 day ago
Select Royal Air Maroc flight, departing Sun, Jul 13 from Seattle to London, returning Sun, Jul 20, priced at $3,392 found 1 day ago
Royal Air Maroc
Sun, Jul 13 - Sun, Jul 20
SEA
Seattle
STN
London
$3,398 Roundtrip, found 1 day ago
$3,398
Roundtrip
found 1 day ago
Select Royal Air Maroc flight, departing Sun, Jul 13 from Seattle to London, returning Sun, Jul 20, priced at $3,398 found 1 day ago
Lufthansa
Sun, Sep 28 - Wed, Oct 8
SEA
Seattle
STN
London
$4,317 Roundtrip, found 4 days ago
$4,317
Roundtrip
found 4 days ago
Select Lufthansa flight, departing Sun, Sep 28 from Seattle to London, returning Wed, Oct 8, priced at $4,317 found 4 days ago
United
Sun, Sep 28 - Wed, Oct 8
SEA
Seattle
STN
London
$4,322 Roundtrip, found 4 days ago
$4,322
Roundtrip
found 4 days ago
Select United flight, departing Sun, Sep 28 from Seattle to London, returning Wed, Oct 8, priced at $4,322 found 4 days ago
Air Canada
Sun, Sep 28 - Wed, Oct 8
SEA
Seattle
STN
London
$4,324 Roundtrip, found 4 days ago
$4,324
Roundtrip
found 4 days ago
Select Air Canada flight, departing Sun, Sep 28 from Seattle to London, returning Wed, Oct 8, priced at $4,324 found 4 days ago
Flights from Seattle (SEA) to London (STN)
Origin airport
Seattle - Tacoma Intl.
Destination airport
Stansted
Airlines serving
Royal Air Maroc
Roundtrip price
$2,257
Distance
4781 mi

Seattle to London Flights

The cheapest times to fly from Seattle to London

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Seattle to London are during the month of July. You can find some of the cheapest flights from Seattle to London with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Seattle to London

Sunday is one of the best days to book for cheap flights from Seattle to London: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Seattle to London

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Seattle to London in 2025. You can also book with separate airlines for your outbound and return journeys, from $441 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Seattle to London flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Seattle to London airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN) cost?
Discover the latest flight deals from SEA to STN by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from SEA to STN?
The cheapest flights from SEA to STN are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from SEA to STN?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from SEA to STN. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN)?
There are no daily nonstop flights departing from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN). But you can book flights with layovers. Filter your search on Expedia to include one or more stops, and you’ll be on your way in no time at all.
What day of the week has the most flights from SEA to STN?
Friday is usually the busiest day for flights, while Tuesday tends to be the quietest.* Just remember that flight schedules can vary based on a number of factors, including the season and airline.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN)?
Select a flight from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN) that leaves before 3 PM to reduce the risk of cancellations. Departures after this time are on average 22% more likely to be canceled.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
What airports do you fly into for London from Seattle - Tacoma Intl. Airport (SEA)?
If you’re traveling on a direct flight from Seattle - Tacoma Intl. Airport (SEA) to London, Heathrow Airport (LHR) is the only airport you can land at.
Is it cheaper to buy a plane ticket from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN) last-minute?
Waiting until just before your trip to book your flight from SEA to STN often results in higher prices. While it’s possible to find some last-minute deals, there’s no guarantee. Keep your travel schedule open for a better chance of getting a bargain.
Is it cheaper to book a SEA to STN flight and hotel package?
Booking a SEA to STN flight and hotel package is generally cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Choose from our impressive range of accommodations and then add flights, car rentals and activities to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Seattle - Tacoma Intl. Airport (SEA) to Stansted Airport (STN)?
If you reserved your SEA to STN flight within the last 24 hours, you may be able to modify or cancel it without fees. Depending on the airline and the type of fare you purchased, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal for further details.

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*Available to One Key members.